[Electronic Supplementary Information]

Fast two-step deposition of perovskite via mediator

extraction treatment for large-area, high-

performance perovskite solar cells

Young Yun Kim, Eun Young Park, Tae-Youl Yang, Jun Hong Noh, Tae Joo Shin, Nam Joong Jeon,

Jangwon Seo*

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Electronic Supplementary Material (ESI) for Journal of Materials Chemistry A.This journal is © The Royal Society of Chemistry 2018

Fig

ure S1. SEM images of PbI2 films and after washing of DMSO by a) heat treatment, c)

chlorobenzene, and e) water. SEM images of MAPbI3 films prepared by subsequent dipping in

MAI solution, for PbI2 films made by b) heat treatment, d) chlorobenzene, and f) water.

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Figure S2. UV-vis spectra of perovskite film with different reaction time, for a) DMF:DMSO = 8:2,

and b) 9:1. c) A photograph of perovskite films with different reaction time, showing fast reaction

for DMF:DMSO = 9:1 than 8:2.

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Figure S3. XRD spectra of MAPbI3 films fabricated by dipping in different concentration of MAI

solutions.

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Fig

ure S4. Azimuthally integrated intensity plots calculated from GI-WAXS spectra.

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Figure S5. Radially integrated intensities of PbI2 films along the (101) plane.

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Figure S6. SEM image of PbI2 film made by washing of DMSO by IPA for 2 min.

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Figure S7. Histogram of PCEs for optimized solar cells made by MET.

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Figure S8. The dark J-V curve.

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Figure S9. EQE spectrum and corresponding integrated photocurrent for the champion device.

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Figure S10. J-V curves of solar cells fabricated by different extraction solvent and treatment.

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Figure S11. Schematic diagram of the structure of solar cells made by using slot-die coating.

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